#include <stdio.h>
 
int main() {
    int b, c, v, sum, k = 0;
 
    // 100～999までのすべての3桁の数について調べる
    for (int i = 100; i < 1000; i++) {
        b = i / 100;        // 百の位
        c = (i / 10) % 10;  // 十の位
        v = i % 10;         // 一の位
 
        sum = b + c + v;    // 各桁の和
 
        if (sum % 7 == 0) {
            k++;  // 7の倍数ならカウント
        }
    }
 
    printf("%d\n", k);
    return 0;
}

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